Hamburg engineer Günter Kupczik’s rotating bend technology was first installed in the Dresden sewer system 30 years ago. Now this unique solution for intelligent sewer management is being further developed in the “Drehbogen 4.0” research project at Hof University of Applied Sciences. The aim is to optimize the technology with digital elements and make it usable as a climate-resilient solution for modern wastewater systems.
Image: Hof University of Applied Sciences;
The rotating bend technology enables improved volume management during heavy rainfall events and automatic sewer cleaning without the need for personnel. The special arch construction with torsion compensator allows water to be dammed up in the sewer in a targeted manner and drained in a controlled manner so that deposits are removed by the wave energy generated and transported directly to the sewage treatment plant. To this day, the rotating bend, together with the so-called ASA weir, is one of the few options for implementing intelligent sewer management without restricting the flow cross-section. And it remains the only technology with the maximum utilization of storage potential in a sewer.
From the sieve grinder to the rotating bend
In the 1980s, Günter Kupczik developed the “Sielwolf system” for cleaning large sewer pipes in Hamburg. The time-consuming disposal of the debris removed in the process led to the search for a more efficient solution. This resulted in the rotary arch, which went into operation for the first time in Dresden in 1994. Although the technology has only been implemented once so far, the demand for innovative sewer management solutions is increasing, particularly as a result of new EU regulations to reduce unfiltered wastewater discharge. The advantage: with modern digitalization options, the potential of rotary kiln technology can now be used more effectively.
“Rotary kiln 4.0” research project
Under the leadership of Prof. Günter Müller-Czygan, the “Water Infrastructure and Digitalization” research group at the Institute for Sustainable Water Systems at Hof University of Applied Sciences (inwa) is working with HST Systemtechnik GmbH & Co. KG to investigate the scalability and further development of the rotating bend. Imam Burhani, a research assistant, is carrying out simulations and calculations as part of his doctorate at the University of Duisburg-Essen.
Collaboration with the inventor
At the working meeting on January 27, 2025 in Dresden, Prof. Günter Müller-Czygan and rotary bow inventor Günter Kupczik discussed the current state of research. Kupczik contributed valuable insights from his decades of experience.
“I am happy that we can continue to develop the rotary bow technology together.”
Günter Kupczik, engineer
Integration into the climate-resilient water infrastructure
The “Drehbogen 4.0” project is part of the “Climate-resilient water infrastructures” research focus at the Institute for Sustainable Water Systems (inwa). The researchers are working on solutions for adapting water management infrastructures to extreme weather events. Prof. Müller-Czygan summarizes:
“It is a pleasure and an honor for us to further develop this innovative technology and integrate it with modern IT elements into sustainable wastewater systems.”
Prof. Günter Müller-Czygan
